Method for preparing a cheese product

ABSTRACT

A method for preparing a no fat or low fat cheese product from a culture medium prepared by combining from about 50 to about 94 wt. % whole milk, from about 0 to about 45 wt. % water, and from about 0.2 to about 1 wt. % of at least one food grade, polyanionic gum. The culture medium is inoculated with at least one lactic acid- or hetero-acid producing bacterium to form a cultured mixture. The cultured mixture is then combined in a vat with skim or low fat milk to form a cultured milk. The cultured milk is ripened, sufficient rennet added to form a coagulum, the coagulum cut to form curd in a whey solution, and the curd cooked while in the whey solution. The cooked curd is transferred to a means for draining the whey solution where the whey is separated from the curd and the curd salted. After salting, the curd is further processed to produce a no fat or low fat cheese.

PRIORITY

This application is a continuation of U.S. patent application Ser. No.09/251,127, filed Feb. 16, 1999, now U.S. Pat. No. 6,258,389, which is acontinuation of U.S. patent application Ser. No. 08/664,435, filed Jun.18, 1996, now U.S. Pat. No. 5,895,671, which claims priority of U.S.Provisional Application Serial No. 60/016,709, filed May 2, 1996.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to the chemical arts. In particular, it relatesto a culture medium and a cultured milk used to make no fat or low fatcheese products and to a method for making such cheese products.

2. Discussion of the Related Art

In recent years, for health as well as cosmetic reasons, there hasdeveloped an increasing concern with diet which has focused on reducedfat consumption. Low fat foods which look and taste like their higherfat counterparts have been eagerly sought by the public. To this end,food researchers have concentrated on developing food products which arenutritious and palatable, but which contain substantially reduced levelsof fat. This is particularly true in the dairy industry where suchreduced fat products as skim milk and yogurt have been successfullymarketed. However, the successes in these areas have not carried over tomethods for preparing no fat or low fat cheeses having high consumeracceptance.

Attempts have been made to use skim or low fat milk in conventionalcheese making processes, to produce no fat or low fat cheeses.Unfortunately, the body, texture and flavor of the resulting no fat orlow fat cheese products have not been entirely satisfactory for ordinaryconsumer use. The cheeses tend to be extremely hard, leathery and tough,and are often almost completely devoid of flavor. Therefore, it is adesideratum for a process which results in the preparation of no fat orlow fat cheese products having similar body, texture and flavor whencompared to their full fat counterparts.

Typically, in the manufacture of no fat or low fat cheese, raw orpasteurized skim or low fat milk is placed in a vat and heated to anappropriate temperature. Bacteria, such as S. cremoris, S. lactis, S.citrovorous, S. thermophillus, L. bulgaricus. L. casei and L.heleveticus, are approved lactic acid- and hetero-acid-producingcultures that when added to the milk begin to produce lactic acid andother products, such as fatty acids, butyrates and octanoates, whicheffect the body, texture and flavor of the final cheese product. To aidin their production, the acid bacteria are often combined with a culturemedium before addition to the milk.

After addition of the bacteria, the milk is allowed to ripen until adesired degree of acid has been produced. The milk at this stage isknown as cultured milk. Rennet is added to the cultured milk to form acoagulum. When the coagulum has reached a desired degree of firmness, itis cut to form curd in a whey solution. The vat is then heated tobetween about 95° F. and 120° F. and held at a temperature in this rangefor a period of time sufficient to cook the curd, causing the curd tocontinue firming and the bacteria to continue producing lactic acid andother products which effect the body, texture and flavor of the finalcheese product. The whey solution is then drained, leaving a firm,resilient curd. The disposal of whey can be a problem and it isdesirable to be able to recycle the whey to the greatest possibleextent. Consequently, it is also a desideratum to maximize the amount ofrecyclable whey that can be recovered from a no fat or low fat cheesemaking process.

After the vat is drained of the whey solution, the curd is salted. Incertain conventional processes, salting cannot occur until afterbacteria have produced sufficient acid to cause the curd to have a pH ofless than 5.5. The addition of salt has the affect, inter alia, ofsignificantly decreasing the bacterial activity, thereby lesseningproduction of additional lactic acid and other products. After salting,the cheese is typically further processed, such as by aging which allowsadditional development of lactic acid and other byproducts effecting thefinal body, texture and flavor of the desired cheese product. Becausethe salting step slows down the production of lactic acid and otherproducts, aging can be a time-consuming process requiring from severalweeks to several years.

It can be appreciated from the above description that the cheese makingprocess is time-consuming, particularly because of the time required forthe pH and flavor of the curd to develop before salting and because ofthe time required to ripen the cheese after it has been salted.Therefore, it is also a desideratum to minimize the time required tomanufacture no fat or low fat cheese with desirable attributes andthereby increase the efficiency of the cheese making process.

Accordingly, there has existed a definite need for an improved methodfor preparing no fat and low fat cheese products having a more similarbody, texture and flavor when compared to their full fat counterparts.There has existed a still further need for an improved method forpreparing no fat or low fat cheese products minimizing the time requiredto produce a final cheese product, while maximizing the amount ofrecyclable whey. The present invention satisfies these and other needsand provides further related advantages.

SUMMARY OF THE INVENTION

In accordance with the invention, there has been found a cheese culturemedium and a cultured milk that enhance the development of lactic acid,hetero-acids and other products of the bacteria used in cheese makingprocesses. Because of the enhanced development, it is possible toproduce reduced fat cheese products having a more similar body, textureand flavor when compared to their full fat counterparts. Further,because of the enhanced development, it is possible to shorten oreliminate various steps required throughout conventional cheese makingprocesses for the production of lactic acid, hetero-acids and otherproducts.

The cheese culture medium contains from about 50 to about 94 wt. %,preferably about 55 to about 65 wt. %, whole milk, from about 0 to about45 wt. %, preferably about 35 to about 45 wt. %, water, and from about0.2 to about 1 wt. %, preferably from about 0.3 to about 0.5 wt. % of atleast one food grade, polyanionic gum, where the weight percents arebased on the total weight of the culture medium. Representative anionicgums include agar, xanthan, alginate, guar, carrageenan, cellulose gels,such as carboxymethyl cellulose, and the like.

In preferred embodiments, the culture medium also contains from about 1to about 4 wt. % of a nonionic thickener, such as a modified foodstarch, from about 0.1 to about 1 wt. % of at least one emulsifing salt,such as sodium citrate, sodium phosphate, dipotassium phosphate orcombinations thereof, and from about 1 to about 5 wt. % of at least onenutrient source, such as yeast extract, yeast autolysate, solubilizedyeast, food yeast, magnesium sulfate, enzyme hydrolyzed casein, aminoacids, proteins, nonfat dry milk, sweet whey powder, simple sugars, suchas lactose, and mixtures thereof, where the weight percents are based onthe total weight of the culture medium. Additional ingredients that canbe included in the culture medium include flavorings, fat mimetics andfat emulsifiers, to decrease the size of the fat droplets and dispersethe fat droplets evenly, and opacifying agents, such as titaniumdioxide.

In accordance with the invention, no fat or low fat cheeses are producedby pasteurizing the culture medium, and then cooling the medium to atemperature suitable for growth of lactic acid-, hetero-acid, orflavor-producing bacteria. The culture medium is then inoculated withlactic acid-, hetero-acid, or flavor-producing bacteria and the mixturedeveloped to form a cultured mixture. Cultured milk is then made byadding, in a vat, from about 3 to about 8 wt. % of the cultured mixture,based on the weight of the cultured milk, to skim or low fat milk. Insome embodiments, flavor promoter, coloring, and/or calcium chloride areadded along with the cultured mixture and the skim or low fat milk. Thecultured milk is allowed to ripen and sufficient rennet is added to theripened milk to form a coagulum. The coagulum is then cut to form curdin a whey solution and the curd cooked, before draining the wheysolution and salting the curd. In some embodiments, at least about 50wt. % of the whey solution is predrawn based on the total weight of wheysolution in the vat, before the curd is transferred from the vat tomeans for draining the whey solution, and the remainder of the wheysolution drained away. And in some embodiments, salting begins when thepH of the curd is 5.6 or greater. After salting, processing is completedto produce a reduced fat cheese having a body, texture and flavor moresimilar when compared to its full fat counterpart.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

To exemplify the process in accordance with the invention, the followingdescription may concentrate primarily on a method for preparing reducedfat mozzarella cheese using, for example, a drain table to finallyseparate the curd from the whey solution. It should be readily apparentto the skilled artisan that the description, with little modification,might also apply to preparing other reduced fat cheeses. For example,low fat or no fat American, cheddar, colby, provolone, and the like canall be prepared in accordance with the inventive method. Further, therecan be modifications in the equipment used. For example, a continuous,perforated belt can be used instead of the drain table to completeseparation of the curd from the whey solution.

The culture medium in accordance with the invention contains from about50 to about 94 wt. %, preferably from about 55 to about 65 wt. %, wholemilk, based on the weight of the culture medium. The term whole milk, asused herein, means milk having a butterfat content of from about 3.0 toabout 4.5 % butterfat, preferably about 3.5 to about 4% butterfat, basedon the weight of the whole milk. The term whole milk also includescombinations of various butterfat content milks and equivalentcompositions formed by suitable admixtures of milk solids and waterhaving comparable butterfat contents. The butterfat content of the milkis important to the practice of the invention. If the milk contains toolittle butterfat, use of the resulting culture medium will not produceno fat or low fat cheeses having the same desirable body, texture andflavor, as cheeses prepared with the culture medium in accordance withthe invention. On the other hand, if the butterfat content of the milkis too great, there is an unnecessary increase in the fat content of thecheese product, without any attendant improvement in its body, textureor flavor.

The culture medium also contains from about 0 to about 45 wt. %,preferably from about 35 to about 45 wt. %, water, based on the weightof the culture medium. The amount of water to be used in a particularapplication is chosen to adjust the viscosity of the culture medium and,ultimately, the viscosity of the culture mixture.

Another ingredient contained in the culture medium is a good grade,polyanionic gum stabilizer. Representative anionic gums include agar,xanthan, alginate, guar, carrageenan, cellulose gels, such ascarboxymethyl cellulose, and the like, as well as mixtures thereof. Thepolyanionic gum stabilizer is added in an amount sufficient to helpstabilize the solids in the subsequently produced culture mixture. Thestabilizer also helps in preventing the resulting curd from having anundesirable rubbery texture. The polyanionic gum stabilizer is typicallyadded to the culture in an amount from about 0.2 to about 1.0 wt. %,preferably from about 0.3, to about 0.5 wt. %, based on the weight ofthe culture medium. Without wishing to be bound by a theory of theinvention, it is believed that by adding the stabilizer to whole milkcertain stabilizer/fat/culture interactions occur which enhance thebody, texture and flavor of the subsequently formed cheese. Suchinteractions are less likely to occur, if they occur at all, when thestabilizer is directly added to skim or low fat milk.

In preferred embodiments, the culture medium also contains from about 1to about 4, preferably from about 2 to about 3 wt. %, of a nonionicthickener, such as a modified food starch, based on the weight of theculture medium. The nonionic thickener is added in an amount sufficientto aid in imparting a softer texture to the resulting curd. The nonionicthickener also develops a soft gel to the culture mixture that preventssolids from separating after the mixture has been added to the mixingvessel.

The culture medium can also contain from about 0.1 to about 1.0 wt. %,preferably from about 0.25 to about 0.5 wt. %, of an emulsifing salt,based on the weight of the culture medium. Emulsifing salts are added inan amount sufficient to buffer the culture media and sequester calcium.Representative salts include monosodium phosphate, disodium phosphate,dipotassium phosphate, trisodium phosphate, sodium metaphosphate (sodiumhexametaphosphate), sodium acid phosphate, tetrasodium pyrophosphate,sodium aluminum phosphate, sodium citrate, potassium citrate, calciumcitrate, sodium tartrate, sodium potassium tartrate and mixturesthereof. Sodium citrate, sodium phosphate or dipotassium phosphate arepreferred. An additional advantage of phosphate-containing emulsifiers,is that the phosphate is a nutrient source for the acid-producingbacteria and of dipotassium phosphate is that potassium is also anutrient source for the acid-producing bacteria.

Other nutrient sources can be added to the culture medium, typically inan amount from about 1 to about 5 wt. %, based on the weight of theculture medium. An amount from about 2 to about 3 wt. % is preferred.Suitable nutrient sources include nitrogen sources, such as yeastextract, yeast autolysate, solubilized yeast, food yeast, enzymehydrolyzed casein, amino acids, and proteins, as well as othernutrients, including nonfat dry milk, sweet whey powder, simple sugars,such as lactose, sodium phosphates and magnesium sulphate.

It is also possible to add flavorings, typically in an amount from about0.1 to about 1.5 wt. %, based on the weight of the culture medium.Flavorings containing little or no fat are preferred, so that they willnot add significantly to the fat content of the final cheese product.Representative no fat or low fat flavorings include buttermilk solidsand natural and artificial butter and dairy flavor components.Additional ingredients that can be included in the culture mediuminclude fat mimetics, such as propylene glycol monoester (which also mayhelp in stabilizing and evenly dispersing the fat) and opacifyingagents, such as titanium dioxide.

The culture medium is made by mixing the ingredients to form a slurry.The slurry is pasteurized, for example, by heating to 190° F. for thirtyseconds. The culture medium is then cooled to a temperature of fromabout 75° F. to about 108° F., preferably about 90° F. to about 96° F.,before inoculating with acid-producing bacteria.

Lactic acid-, hetero-acid, and flavor-producing bacteria for use incheese making are well known in the art and the choice of a particularbacterium or combination of bacteria will depend on the type of cheeseto be produced. Representative bacteria suitable for practice of theinvention include, without limitation, S. cremoris, S. lactis, S.citrovorous, S. paracitrovorous, S. thermophillus, S. durans, S.diacetilactis, S. faecalis, L. acidophilus, L. bulgaricus, L. brevis, L.casei, L. delbruekii, L. fermenti, L. heleveticus, L. lactis, L.plantarum, L. thermophillus, leuconsostoc eitrovorum, leuconsostocmesenteroides, Bacteriumlinesn, Micrococcus caseolyticus, Pediococcuscerevisiae, Pseudomonas fraga and propionibacterium species, such asPropionibacterium shermanii. In the manufacture of no fat or low fatmozzarella cheese, L. casei or a combination of S. thermophillus and L.bulgaricus are preferred.

While maintaining the elevated temperature, the mixture is developed forseveral hours, until a pH from about 4.8 to about 4.6, preferably about4.7 is attained. The resulting cultured mixture is cooled, whilecontinuously stirring, to a temperature of from about 40° F. to about48° F., preferably about 45° F., and a pH of from about 4.7 to about4.4, preferably about 4.6.

In contrast to the whole milk used to form the culture medium, in themaking of the cultured milk, the cultured mixture is added to skim milk(milk having a butterfat content less than 0.5%) or low fat milk (milkhaving a butterfat content less than 2.0%). As used herein, skim and lowfat milks include equivalent compositions formed by suitable admixturesof milk solids and water. The skim milk can be raw milk, but ispreferably pasteurized and fortified to a desired vat protein level.Typically, cultured milk is formed by adding from about 3 to about 8 wt.% cultured mixture, preferably about 5 to about 7 wt. % culturedmixture, based on the weight of the cultured milk, to skim or low fatmilk having a temperature of from about 75° F. to about 108° F.,preferably about 96° F. It is an advantage of the process in accordancewith the invention that the skim milk or low fat milk can have anybutterfat level below the final desired butterfat level and then thefinal butterfat level simply and reliably achieved by adding therequisite amount of the whole milk-based cultured mixture. The finalbutterfat level in the vat is normally in the range of from about 0.1 toabout 0.5%, preferably from about 0.2 to about 0.3%, based on the weightof the cultured milk, depending on the desired fat content of the finalcheese product.

Other ingredients can be added along with the cultured mixture and wholemilk into a stainless steel vat or similar mixing vessel. For example,the cultured milk mixture can include from about 0.005 to about 0.02 wt.% calcium chloride, based on the weight of the cultured milk. Thecalcium chloride can be added in dry form, but it is preferably added inthe form of an aqueous solution. The period of ripening is affected bythe presence of calcium chloride; the absence of calcium prolonging theripening period. The added calcium chloride also serves to replacenatural calcium chloride lost from the milk. The cultured milk can alsoinclude such conventional ingredients as flavor promoters and colorings.Ingredients, such as flavorings and opacifying agents, if not added tothe cultured mixture, can also be added or they can be added in additionto the amounts included in the cultured mixture.

The cultured milk is then ripened by maintaining the temperature betweenabout 75° F. and about 98° F., preferably between about 95° F. and about98° F., with stirring, for about 15 to about 40 minutes, preferablyabout 35 minutes. The pH of the ripened milk at the end of this periodis generally from about 6.35 to about 6.65.

A clotting enzyme is mixed into the ripened milk to cause the milk tocoagulate. Suitable clotting enzymes include rennet, rennin, a dilutedrennin extract, a pepsin-rennin mixture, a vegetable-derived enzymeclotting agent or the like. Rennet is preferred. Other enzymes such aspepsin and papain may be used alone or in combination with the rennet orrennin. After addition of the clotting enzyme, the mixture is allowed toset without stirring for about 20 to 40 minutes, typically about 30minutes, to form a firm, set coagulum.

Once set, the coagulum is cut. It is first cut mechanically usingvertical and horizontal curd knives. After removal of the curd knives,it is manually cross-cut with a vertical knife. Cutting of the stablecoagulum causes whey syneresis and leads to a heterogeneous mixture ofcurd in a whey solution.

The curd is then cooked, while in the whey solution. For no fat or lowfat mozzarella cheese, the temperature of the curd in the whey solutionis gradually raised from about 96° F. to about 118° F., preferably about106° F., within a period from about 20 about 40 minutes, preferably,from about 30 to about 35 minutes.

Shortly after cooking and before the curd is transferred to a drainingtable, up to about 50%, typically up to about 35%, of the whey solutionis predrawn from the curd. This step has the advantage of producingunadulterated whey, especially suitable for recycling. The curd and theremainder of the whey solution are then transferred to a draining table.As the mixture is stirred the remaining whey solution is drained fromthe curd and the curd salted.

In certain conventional processes, salting does not occur until afterbacteria have produced sufficient lactic acid to cause the curd to havea pH of less than 5.5. It is an advantage of the inventive process thatsalting can begin, without waiting for the pH to drop to less than 5.5.For example, in the preparation of reduced fat cheddar cheeses, the curdcan be salted when it has a pH of 5.6 or greater.

After salting are a number of steps particularly suited for thepreparation of mozzarella cheese. The salted curd is conveyed to amozzarella-type, steam injected cooker and heated to form a homogeneous,thermoplastic mass with an internal temperature of about 140° F. Thecheese mass is then sent through a molder to make loaf- or ball-shapedforms.

The formed cheese is chilled by conveying through a chill tank. Thecheese is then removed from its form and further chilled and salted bypassing through a brine tank. Lastly, the cheese is drained and thenpackaged.

Alternatively, the thermoplastic mass can be conveyed through a separatemolder followed by a string-forming extruder. The resulting strings arecut into pieces and the pieces are then passed through a brine tank,drained, and packaged.

In contrast, if the desired no fat or low fat cheese is a cheddarcheese, the salted cheese curd is transferred directly to forms, hoops,or barrels. The cheese is then pressed to expel entrapped whey andallowed to knit. After knitting the cheese is aged.

The following examples are included to further illustrate the invention.They are not a limitation thereon. All percentages are based on weightunless otherwise clearly indicated.

EXAMPLE 1

A no fat mozzarella cheese is prepared by the following method.

Preparation of Culture Medium

The following ingredients are mixed to form a slurry: 58.7% whole milk,35.8% water, 4.3% Bunge Stabilset, 0.2% dipotassium phosphate, 1.0%Pfizer Autostat, and 0.2% natural flavor. Bunge Stabilset (availablefrom Dari-Tech Industries, Atlanta, Ga.) is an admixture of agar,xanthan gum, cellulose gel, locust bean gum, modified food starch,sodium phosphate, sodium citrate, propylene glycol monoester, andtitanium dioxide. Pfizer Autostat is a nutrient source (available fromPfizer, Milwaukee, Wis.) containing a soluble growth factor from S.cerevisiae, lactose, disodium phosphate and magnesium sulphate. Theresulting slurry is pasteurized to 190° F. for 30 seconds and thencooled to 106° F.

Preparation of Cultured Mixture

The slurry is inoculated with 1.0% of a mixture of S. thermophillus andL. bulgaricus bacteria based on the weight of the cultured mixture. Thebacteria are allowed to grow for several hours until the pH reaches 4.8.The cultured mixture is then continuously stirred, while cooling to 45°F. At this point a final pH of 4.7 is attained.

Preparation of Skim Milk

Whole milk is standardized to 3.6% vat protein by fortifying with nonfatdry milk. The fortified milk is then skimmed to the lowest possible fatlevel (0.05-0.07%) in a milk separator. The separated milk ispasteurized to 164° F. for 17 seconds and then passed through avacuutherm to cool the milk to 96° F.

Preparation of Mozzarella Curd

Fifteen hundred pounds of the cultured mixture are added to a stainlessvat as the vat receives about 31,000 pounds of skim milk at a rate ofabout 51,000 pounds per hour. The following ingredients are also addedat this time: two cans (360 mls each) of flavor promoter, L. casei(LF304, available from Cultor Foods, Milwaukee, Wis.), 0.75 oz. ofAnnatto cheese color and 11.89 pounds of 30% aqueous calcium chloride(Cal Sol, available from Systems Bio Industries, Waukesha, Wis.). Thecombined ingredients are stirred and allowed to ripen for about 35minutes from the time the cultured mixture is added, achieving a pH ofabout 6.6 and a titratable acidity of about 0.2%.

After ripening, 30 oz. of double strength rennet (Maxiren, availablefrom Gist Brocades, Menomonee Falls, Wis.), diluted with 10 times thevolume of water, is poured into the ripened blend, along the length ofthe vat. The blend is mixed with an agitator until the rennet is evenlydistributed in the milk and then allowed to set without stirring forabout 30 minutes.

Once the blend becomes a firm, set coagulum, it is cut mechanicallyusing an ½″ vertical and a ⅜″ horizontal set of curd knives. Formationof a curd in a whey solution begins as the stable coagulum is cut. Thecurd knives are carefully removed and the curd is cross-cut manuallywith an ½″ vertical knife.

The resulting mixture of curd in a whey solution is stirred for about 10minutes and then, with continued, continuous stirring is cooked bygradually increasing the temperature from 92° F.-104° F. within a periodof about 35 minutes.

Ten minutes after cooking is completed, about one-third of the wheysolution is drawn from the vat. The residual whey solution and the curdare then transferred by gravity to a draining table and the remainingwhey solution immediately, completely drained. The pH at this point isabout 6.15 and the titratable acidity about 0.17-0.19%. The drained curdis stirred until a pH of about 5.35 and a titratable acidity of about0.45-0.50% is reached. Then 50 pounds of salt is evenly distributedacross the curd in two application of 25 pounds and the stirringcontinued for 10 minutes.

Preparation of Mozzarella

The curd is conveyed to a mozzarella-type, steam-injected cookercontaining water heated to 185-190° F., where the curd forms ahomogeneous, thermoplastic mass with an internal temperature of about138° F. The cheese mass is then sent through a molder into loaf-shapedforms.

The formed cheese is chilled by conveying through a chill tank. Thecheese is then removed from its form and further chilled and salted bypassing through a brine tank. Lastly, the cheese is drained and thenpackaged. The no fat cheese produced in accordance with this example hasa body, texture and flavor that compares very favorably with its fullfat counterpart.

EXAMPLE 2

A no fat mozzarella cheese is prepared by the following method.

Preparation of Cultured Medium

Culture Medium A

The following ingredients are mixed to form a slurry: 89% water, 10%sweet whey powder, and 1% Pfizer Autostat. The resulting slurry ispasteurized to 185° F. for 30 minutes and then cooled to 106° F.

Culture Medium B

The following ingredients are mixed to form a slurry: 59% whole milk.35.75% water. 4% Bunge Stabilset, 1% dipotassium phosphate, and 0.25%Pfizer Autostat. The resulting slurry is pasteurized to 190° F. and thencooled to 90° F.

Preparation of Cultured Mixture

Cultured Mixture A

Culture medium A is inoculated with 1.00% of a mixture of S.Thermophillus and L. bulgaricus bacteria. The bacteria are allowed togrow for several hours until the pH reaches 4.60. The cultured mixtureis then continuously stirred, while cooling to 45° F. At this point a pHof 4.50 is attained.

Cultured Mixture B

Culture medium B is inoculated with L. casei (PLCI, available fromCultor Foods, Milwaukee, Wis.). The bacteria are allowed to grow forfour hours and then cooled with stirring to a temperature of 45° F. Atthis point, the acid-producing bacteria have acclimated from the frozenstate and multiplied several generations.

Preparation of Curd

Three hundred pounds of cultured mixture A, 2300 pounds of culturedmixture B, and 50 ounces Cal Sol, 30% calcium chloride, are added to adouble O vat as the vat receives about 45,000 pounds of skim milkprepared in accordance with Example 1. The combined ingredients arestirred and allowed to ripen for about 40 minutes from the time thecultured mixture is added, achieving a pH of about 6.40 and a titratableacidity of about 0.21%.

After ripening, 26 oz. of Maxiren, double strength rennet, diluted with10 times the volume of water is poured into the ripened blend, along thelength of the vat. The blend is mixed with an agitator set at 5½ rpms,for 2 minutes, then allowed to set without stirring for thirty minutes.Formation of a curd in a whey solution begins as the stable coagulum iscut as explained in Example 1.

The resulting mixture of curd in a whey solution is stirred for about 5minutes, at 6½ rpms and then, with continued, continuous stirring iscooked by gradually increasing the temperature from 96° F. to 100° F.with a gradual increase in agitator speed to 8½ rpms. Stirring thencontinues as the agitator speed is brought to 10½ rpms and thetemperature is brought to 110° F.

After cooking is completed, the stirring is continued, until a pH of6.10 is achieved. The curd in the whey solution is then pumped by apositive pump to an inclined draining belt where all the whey solutionis immediately drained. The curd, at this point, has a pH of 6.00. Thecurd is then piled onto a continuously moving belt for 30 minutes andthe pH developed to below 5.50. After 25 minutes on the belt, the curdis salted.

Preparation of Cheese

The salted curd is cut and transferred to a cooker/mixer where it iscooked in 180° F. water to produce a molten cheese having a temperatureof 135-140° F. The resulting molten cheese is poured into an extruderand loaves are formed.

The loaves are cooled in chilled water for 30 minutes and thentransferred for further cooling and salting in a 90% salinity brine forover 3½ hours. The product is then washed, drained, and packaged. The nofat cheese produced in accordance with this example has a body, texture,and flavor that compares very favorably with full fat cheese.

We claim:
 1. A method for preparing a cheese product comprising thesteps of: preparing a culture medium by combining whole milk, at leastone food grade polyanionic gum, and optionally water; pasteurizing theculture medium; cooling the pasteurized culture medium to a temperaturesuitable for the growth of acid-producing bacteria; inoculating theculture medium with at least one acid-producing bacteria; developing andthen cooling the thus formed mixture, to form a cultured mixture;forming cultured milk by mixing the cultured mixture with skim or lowfat milk; ripening the cultured milk; a adding sufficient rennet to theripened milk to form a coagulum; cutting the coagulum to form curd in awhey solution; cooking the curd while in the whey solution; transferringthe curd in the whey solution to a means for draining the whey solutionand then draining the whey solution from the curd; salting the curd; andfurther processing the salted curd to produce a cheese product.
 2. Themethod of claim 1, wherein the cultured mixture is mixed with low fatmilk having a butterfat content less than about 2 wt. %.
 3. The methodof claim 1, wherein the cultured mixture is mixed with skim or low fatmilk having a butterfat content ranging from about 0.1 to about 0.5 wt.%.
 4. The method of claim 1, wherein the whole milk has a butterfatcontent ranging from about 3.0 to about 4.5 wt. %.
 5. The method ofclaim 1, wherein the whole milk has a butterfat content ranging fromabout 3.5 to about 4.0 wt. %.
 6. The method of claim 1, wherein thewhole milk is present in the culture medium in an amount ranging fromabout 50 to about 94 wt. %, based on the weight of the culture medium.7. The method of claim 1, wherein the culture medium contains water in apositive amount up to about 45 wt. %, based on the weight of the culturemedium.
 8. The method of claim 1, wherein the at least one food gradepolyanionic gum is present in the culture medium in an amount rangingfrom about 0.2 to about 1 wt. %, based on the weight of the culturemedium.
 9. The method of claim 1, wherein the at least one food gradepolyanionic gum is selected from the group consisting of agar, xanthan,alginate, guar, carrageenan, and cellulose gels.
 10. The method of claim1, wherein the at least one acid-producing bacteria is selected from thegroup consisting of S. cremoris, S. lactis, S. citrovorous, S.paracitrovorus, S. thermophillus, S. durans, S. diacetilactis, S.faecalis, L. acidophilus, L. bulgaricus, L. brevis, L. casei, L.delbruekii, L. fermenti, L. heleveticus, L. lactis, L. plantarum, L.thermophillus, leuconsostoc eitrovorum, leuconsostoc mesenteroides,Bacteriumlinesn, Micrococcus caseolyticus, Pediococcus cerevisiae,Pseudomonas fraga and propionibacterium species.
 11. The method of claim1, wherein the cultured mixture has a pH ranging from about 4.6 to about4.8.
 12. The method of claim 1, wherein the amount of skim or low fatmilk mixed with the cultured mixture ranges from about 3 to about 8 wt.% milk, based on the weight of the cultured milk.
 13. The method ofclaim 1, further comprising adding to the culture medium a non-ionicthickener.
 14. The method of claim 13, wherein the non-ionic thickeneris added in an amount ranging from about 1 to about 4 wt. %, based onthe weight of the culture medium.
 15. The method of claim 13, whereinthe non ionic thickener is a modified food starch.
 16. The method ofclaim 1, further comprising adding to the culture medium at least oneemulsifying salt selected from the group consisting of monosodiumphosphate, disodium phosphate, dipotassium phosphate, trisodiumphosphate, sodium metaphosphate, sodium acid phosphate, tetrasodiumpyrophosphate, sodium aluminum phosphate, sodium citrate, potassiumcitrate, calcium citrate, sodium tartrate, sodium potassium tartrate,and mixtures thereof.
 17. The method of claim 16, wherein the at leastone emulsifying salt is added in a total amount ranging from about 0.1to about 1 wt. %, based on the weight of the culture medium.
 18. Themethod of claim 1, further comprising adding to the culture medium atleast one nutrient source for the lactic acid-forming bacteria selectedfrom the group consisting of yeast extract, yeast autolysate,solubilized yeast, food yeast, enzyme hydrolyzed casein, sodiumphosphates, magnesium sulphate and mixtures thereof.
 19. The method ofclaim 18, wherein the at least one nutrient source is added in a totalamount ranging from about 1 to about 5 wt. %, based on the weight of theculture medium.
 20. The method of claim 1, further comprising predrawingup to about 50 wt. % of the whey solution, after cooking and beforetransferring the whey solution to the means for draining whey solution.21. The method of claim 1, wherein the curd is salted when the curdreaches a pH of at least about 5.6.
 22. A method for preparing a cheeseproduct comprising the steps of: preparing a culture medium bycombining: whole milk in an amount ranging from about 50 to about 94 wt.%, based on the weight of the culture medium; at least one food gradepolyanionic gum in an amount ranging from about 0.2 to about 1 wt. %,based on the weight of the culture medium; and optionally water in anamount up to about 45 wt. %, based on the weight of the culture medium;pasteurizing the culture medium; cooling the pasteurized culture mediumto a temperature suitable for the growth of acid-producing bacteria;inoculating the culture medium with at least one acid-producingbacteria; developing and then cooling the thus formed mixture, to form acultured mixture; forming cultured milk by mixing the cultured mixturewith skim or low fat milk having a butterfat content less than about 2wt. %; ripening the cultured milk; adding sufficient rennet to theripened milk to form a coagulum; cutting the coagulum to form curd in awhey solution; cooking the curd while in the whey solution; transferringthe curd in the whey solution to a means for draining the whey solutionand then draining the whey solution from the curd; salting the curd; andfurther processing the salted curd to produce a cheese product.
 23. Themethod of claim 22, wherein the cultured mixture is mixed with skim orlow fat milk having a butterfat content ranging from about 0.1 to about0.5 wt. %.
 24. The method of claim 22, wherein the whole milk has abutterfat content ranging from about 3.0 to about 4.5 wt. %.
 25. Themethod of claim 22, wherein the whole milk has a butterfat contentranging from about 3.5 to about 4.0 wt. %.
 26. A method for preparing acheese product comprising the steps of: preparing a culture medium bycombining: whole milk in an amount ranging from about 50 to about 94 wt.%, based on the weight of the culture medium; at least one food gradepolyanionic gum in an amount ranging from about 0.2 to about 1 wt. %,based on the weight of the culture medium, wherein the at least one foodgrade polyanionic gum is selected from the group consisting of agar,xanthan, alginate, guar, carrageenan, and cellulose gels; and optionallywater in an amount up to about 45 wt. %, based on the weight of theculture medium; pasteurizing the culture medium; cooling the pasteurizedculture medium to a temperature suitable for the growth ofacid-producing bacteria; inoculating the culture medium with at leastone acid-producing bacteria selected from the group consisting of S.cremoris, S. lactis, S. citrovorous, S. paracitrovorus, S.thermophillus, S. durans, S. diacetilactis, S. faecalis, L. acidophilus,L. bulgaricus, L. brevis, L. casei, L. delbruekii, L. fermenti, L.heleveticus, L. lactis, L. plantarum, L. thermophillus, leuconsostoceitrovorum, leuconsostoc mesenteroides, Bacteriumlinesn, Micrococcuscaseolyticus, Pediococcus cerevisiae, Pseudomonas fraga andpropionibacterium species; developing and then cooling the thus formedmixture, to form a cultured mixture having a pH of from about 4.6 toabout 4.8; forming cultured milk by mixing the cultured mixture withskim or low fat milk having a butterfat content less than about 2%,wherein the skim or low fat milk is present in an amount ranging fromabout 3 to about 8 wt. % based on the weight of the cultured milk;ripening the cultured milk; adding sufficient rennet to the ripened milkto form a coagulum; cutting the coagulum to form curd in a wheysolution; cooking the curd while in the whey solution; transferring thecurd in the whey solution to a means for draining the whey solution andthen draining the whey solution from the curd; salting the curd; andfurther processing the salted curd to produce a cheese product.
 27. Amethod for preparing a cheese product comprising the steps of: preparinga culture medium by combining: from about 55 to about 65 wt. % wholemilk, based on the weight of the culture medium, the whole milk having abutterfat content of from about 3.0 to about 4.5 wt. %, based on theweight of the whole milk, from about 35 to about 45 wt. % water, basedon the weight of the culture medium, from about 0.3 to about 0.5 wt. %,based on the weight of the culture medium, of at least one food grade,polyanionic gum selected from the group comprising agar, xanthan,alginate, guar, carrageenan, and cellulose gels; from about 2 to about 3wt. %, based on the weight of the culture medium, of a modified foodstarch; from about 0.25 to about 0.5 wt. %, based on the weight of theculture medium, of at least one emulsifying salt selected from sodiumcitrate, sodium phosphate, dipotassium phosphate or mixtures thereof;and from about 2 to about 3 wt. %, based on the weight of the culturemedium, of at least one nutrient source for lactic acid-producingbacteria selected from yeast extract, yeast autolysate, solubilizedyeast, food yeast, enzyme hydrolyzed casein, sodium phosphates,magnesium sulphate or mixtures thereof; pasteurizing the culture medium;cooling the pasteurized culture medium to a temperature suitable for thegrowth of acid-producing bacteria; inoculating the culture medium withat least one acid-producing bacteria selected from the group consistingof S. cremoris, S. lactis, S. citrovorous, S. paracitrovorus, S.thermophillus, S. durans, S. diacetilactis, S. faecalis, L. acidophilus,L. bulgaricus, L. brevis, L. casei, L. delbruekii, L. fermenti, L.heleveticus, L. lactis, L. plantarum, L. thermophillus, leuconsostoceitrovorum, leuconsostoc mesenteroides, Bacteriumlinesn, Micrococcuscaseolyticus, Pediococcus cerevisiae, Pseudomonas fraga andpropionibacterium species; developing and then cooling the thus formedmixture to form a cultured mixture having a pH of from about 4.8 toabout 4.6; forming cultured milk by mixing from about 5 to about 7 wt. %milk, based on the weight of the cultured milk, with skim or low fatmilk having a butterfat content less than 2%; ripening the culturedmilk; adding sufficient rennet to the ripened milk to form a coagulum;cutting the coagulum to form curd in a whey solution; cooking the curdwhile in the whey solution; drawing up to about 35 wt. % of the wheysolution; transferring the curd and the remaining whey solution to ameans for draining the whey solution; and thereafter draining theremaining whey solution from the curd; salting the curd, when the curdhas a pH of at least about 5.6; and further processing the salted curdto produce a cheese product.